Wire fabric joint and method of producing same



Dec. 27, 1938. w. E. BUCHANAN v 2,141,706

L WIRE FABRIC JOINT AND METHOD OF PRODUCING SAME Filed April 10, 1957 INVENTOR WITNESSES w/Vacu, & AW

B. respectively.

Patented Dec. 27, 1938 UNITED STATES PATENT OFFICE WIRE FABRIC JOINT AND METHOD OF PRODUCING SAME Application April 10, 1937, Serial No. 136,091

8 Claims.

The invention relates to'woven wire fabrics, such as Fourdrinier wires, and more particularly to wire joints and to a method of producing the same.

In certain paper making operations it is found desirable to use a Fourdrinier wire with a very open joint having no transverse obstructions, so as to avoid interference with drainage. In the case of a brazed or soldered joint it has heretofore been found diflicult to avoid such obstructions because of flowing, spreading, or bridging of fusiblemetal in the meshes of the joint or along weft or filler wires adjacent the joint.

It is an object of the present invention to provide an improved soldered or brazed wire fabric joint which is of open and flexible character and yet mechanically strong and durable.

Another object of the invention is to provide a soldered or brazed wire fabric joint forming mesh openings which are relatively free from transverse obstructions or projections.

A further object of the invention is to provide an improved method of producing the joint whereby a reliable union is readily effected with a relatively small amount of fusible metal and without excessive spreading of the fusible metal.

The invention further consists in the several features hereinafter described and claimed.

In the accompanying drawing, illustrating a joint and method of the invention,

Fig. 1 is a top plan view of a woven wire fabric with a joint embodying the invention constructed by the method of the invention, the fabric being shown on a greatly enlarged scale;

Fig. 2 is a sectional view taken along the line 2-2 of Fig.- 1, showing the wire fabric before the joint is completed, and

Fig. 3 is a sectional view taken along the line 33 of Fig. 1, showing the completed joint.

In the drawing, Ill designates the warp wires of a Fourdrinier wire fabric and l l the weft wires thereof, the two ends of the fabric to be joined to form an endless belt being indicated by A and The fabric is here shown to be made in twill weave, but it will be understood that the fabric may also be made in plain weave.

In trimming the ends of the fabric preparatory to forming the joint, the warp wires ll] of each of the ends A and B are out along a line parallel to the weft wires and at a distance from the last weft wire so as to presentprojecting warp ends. The warp ends shown in the drawing have been out rather long. In each fabric part, the warp ends project a substantially uniform distance from the last weft wire, so that the extremities of the warp ends lie in a common plane perpendicular to the plane of the fabric part. Preferably, the warp ends of both fabric parts have the same length.

In carrying outthe method, a strand I2 of a suitable fusible metal, such as silver' solder,

is placed between and along spaced edges of the fabric, the fusible metal having a melting point lower than that of the fabric wires. The strand l2'is preferably in the form of a very fine narrow strip or ribbon, the plane of which is substantially perpendicular to the plane of the cloth. The fabric edges are then urged relatively toward each other to bring the substantially flat end faces of the warp ends thereof into firm contact with the opposite side faces of the fusible strip l2, as shown in the. middle portion of Fig. 1 and also in Fig. 2. The opposing warp ends of the two fabric edges are substantially aligned. Heat is then applied to the fusible strip and to the warp ends, as by means of a traveling gas flame, to fuse the metal of the strip, causing the fine strip to separate or divide into very small masses or deposits of fusible metal which form thin films l2 between the cut end faces of the opposing warp ends, firmly uniting the edges of the fabric. These films are seen in the left-hand part of Fig. 1, and also in Fig. 3. At the time of fusion the fabric ends are pressed relatively toward each other, The excess fusible metal in each of the separated masses or deposits forms a very thin, smooth film II" on or around the united warp ends and does not appreciably thicken the warp ends. This excess metal flows along the warp ends but preferably does not reach or flow along either of the end weft wires, as there are certain cases where very slight transverse obstructions caused by flowing of fusible metal on the end weft wires, or in the crimps thereof, may cause trouble in paper making. The cut ends of the warp wires are covered by the fused metal, thus producing smooth surfaces on which pulp particles will not become lodged. Because the fusible metal strip is very line the fusible metal flows directly to the Warp ends and does not leave a thread or bridge of fusible metal between laterally adjacent warp ends. The numerous opposing pairs of united warp ends each receive substantially the same amount of fusible metal. As indicated in Fig. 1, the several steps may be performed simultaneously at different parts of the wire fabric, the fusible metal strip being progressively interposed between the spaced edges of the fabric, the fabric edges being progressively urged into contact with the strip, and thestrlp being fused progressively along the strip-engaging edges of the fabric. This progressive action is disclosed in general in my United States Patent No. 1, issued January 31, 1933.

By making the projecting warp ends of a suitablelength the joint can be made to duplicate the drainage characteristics of the body of the wire fabric, and by making the warp ends longer a very open joint can be produced. In either case the joint is relatively free from. transverse obstructions or projections which may cause trouble in paper making.

By way of example, for a Fourdrinier wire fabric having about 65 warp threads to the inch, a strip of silver solder .00075 inch thick and .022 inch wide would be suitable for use in producing a point in accordance with the invention.

What I claim as new and desire to secure by Letters Patent is:

1. A wire fabric comprising fabric parts each having warp and weft wires and each having warp ends extending a substantially uniform distance beyond the end weft wire, the warp ends of the fabric parts being arranged in opposed pairs, and small deposits of fusible metal joining the respective opposed pairs of warp ends and having a melting point lower than that of the warp wires, the deposits of fusible metal on laterally adjacent warp end pairs being-spaced from each other, and the joint between each pair of warp ends having approximately the same cross-sectional area as that of the warp wires in the body of the fabric.

2. A wire fabric comprising fabric parts each having warp and weft wires and each having warp ends projecting a substantially uniform distance beyond the end weft wire, the warp ends of the fabric parts being arranged in opposed pairs, and a small deposit of fusible metal joining each opposed pair of warp ends and having a melting point lower than that of the warp wires, some of said deposit of fusible metal being interposed between the opposed warp ends and the rest of said deposit forming a thin film extending along the warp ends, the deposits of fusible metal on laterally adjacent warp end pairs being spaced from each other.

3. A wire fabric comprising fabric parts each having warp and weft wires and each having.

warp ends projecting a substantially uniform distance beyond the end weft wire, the warp ends of the fabric parts being arranged in opposed pairs, and a small deposit of fusible metal joining each opposed pair of warp ends and having a melting point lower than that of the fabric wires, some of said deposit of fusible metal being interposed between the opposed warp ends and the rest of said deposit forming a thin film extending along the warp ends but spaced from the end weft wires, the deposits of fusible metal on laterally adjacent warp end pairs being spaced from each other. Y

4. The method of producing a joint in a wire fabric, which consists in forming projecting wire ends on the two fabric edges to be joined, interposing a fusible metal strand between the fabric edges, placing the wire ends against opposite sides of the strand, the opposed wire ends being substantially aligned, and melting the fusible metal strand to separate it into spaced deposits joining the opposed wire ends.

5. The method of producing a joint in a wire fabric, which consists in forming projecting warp ends on the two fabric edges to be joined, interposing a fusible strand between the fabric edges, placing the warp ends against opposite sides of the strand, the opposed warp ends being substantially aligned, and melting the fusible metal strand to separate it into spaced deposits joining the opposed warp ends and spaced from the end weft wires.

6. The method of producing a joint in a wire fabric having edges with projecting wire ends, which consists in interposing a fusible metal strand between the edges of the fabric parts to be joined and in engagement with opposed wire ends, and melting the fusible metal strand to separate it into spaced deposits joining the opposed wire ends.

7. The method of producing a joint in a wire fabric having edges with projecting wire ends, which consists in interposing a fusiblemetal strand between the edges of the fabric parts, the wire ends being substantially aligned, and melting the fusible metal strand to separate it into spaced deposits joining the aligned wire ends.

8. A woven wire fabric for paper making machines, comprising fabric parts having edges with projecting wire ends, the wire ends of the fabric parts being arranged in opposed pairs, and the extremities of the projecting wire ends of each fabric part lying in a common plane perpendicular to the plane of the fabric part, and small deposits of fusible metal joiningvthe respective opposed pairs of wire ends and having a melting point lower than that of the fabric wires, the deposits of fusible metal on laterally adjacent wire end pairs being spaced from each other.

WILLIAM E. BUCHANAN. 

